hello guys: I have an app which consumes json messages from kafka and recommend movies for the users in those messages ,the code like this :
conf.setAppName("KafkaStreaming") val storageLevel = StorageLevel.DISK_ONLY val ssc = new StreamingContext(conf, Seconds(batchInterval.toInt / 1000)) val kafkaStream = KafkaUtils.createStream(ssc, zkQuorum, group, topicMap, storageLevel) val topicMap = topics.split(",").map((_, numThreads.toInt)).toMap kafkaStream.foreachRDD { rdd => val sqlContext = SQLContext.getOrCreate(rdd.sparkContext) val ALSModel = MatrixFactorizationModel.load(rdd.sparkContext, "/user/hadoop/model/myCollaborativeFilter20160802/") val recRdd = sqlContext.read.json(rdd.values) val getRecResult = org.apache.spark.sql.functions.udf((x: Long) => ALSModel.recommendProducts(x.toInt, 10).mkString ) val resultDF = recRdd.withColumn("recommandresult", getRecResult(recRdd.col("userid")))// val resultDF2 = recRdd.map { x => // ALSModel.recommendProducts(x.getLong(3).toInt, 10) // } println("output result:") resultDF.collect.foreach(println) } ssc.start() ssc.awaitTermination() here are the logs of my app:16/08/03 14:40:49 WARN TaskSetManager: Lost task 0.0 in stage 20.0 (TID 133, slave62): org.apache.spark.SparkException: RDD transformations and actions can only be invoked by the driver, not inside of other transformations; for example, rdd1.map(x => rdd2.values.count() * x) is invalid because the values transformation and count action cannot be performed inside of the rdd1.map transformation. For more information, see SPARK-5063. at org.apache.spark.rdd.RDD.org$apache$spark$rdd$RDD$$sc(RDD.scala:87) at org.apache.spark.rdd.RDD.withScope(RDD.scala:316) at org.apache.spark.rdd.PairRDDFunctions.lookup(PairRDDFunctions.scala:928) at org.apache.spark.mllib.recommendation.MatrixFactorizationModel.recommendProducts(MatrixFactorizationModel.scala:168) at org.brave.spark.streaming.KafkaSparkStreaming2$$anonfun$main$1$$anonfun$2.apply(KafkaSparkStreaming2.scala:51) at org.brave.spark.streaming.KafkaSparkStreaming2$$anonfun$main$1$$anonfun$2.apply(KafkaSparkStreaming2.scala:50) at org.apache.spark.sql.catalyst.expressions.GeneratedClass$SpecificUnsafeProjection.apply(Unknown Source) at org.apache.spark.sql.execution.Project$$anonfun$1$$anonfun$apply$1.apply(basicOperators.scala:51) at org.apache.spark.sql.execution.Project$$anonfun$1$$anonfun$apply$1.apply(basicOperators.scala:49) at scala.collection.Iterator$$anon$11.next(Iterator.scala:328) at scala.collection.Iterator$$anon$11.next(Iterator.scala:328) at scala.collection.Iterator$class.foreach(Iterator.scala:727) at scala.collection.AbstractIterator.foreach(Iterator.scala:1157) at scala.collection.generic.Growable$class.$plus$plus$eq(Growable.scala:48) at scala.collection.mutable.ArrayBuffer.$plus$plus$eq(ArrayBuffer.scala:103) at scala.collection.mutable.ArrayBuffer.$plus$plus$eq(ArrayBuffer.scala:47) at scala.collection.TraversableOnce$class.to(TraversableOnce.scala:273) at scala.collection.AbstractIterator.to(Iterator.scala:1157) at scala.collection.TraversableOnce$class.toBuffer(TraversableOnce.scala:265) at scala.collection.AbstractIterator.toBuffer(Iterator.scala:1157) at scala.collection.TraversableOnce$class.toArray(TraversableOnce.scala:252) at scala.collection.AbstractIterator.toArray(Iterator.scala:1157) at org.apache.spark.rdd.RDD$$anonfun$collect$1$$anonfun$12.apply(RDD.scala:927) at org.apache.spark.rdd.RDD$$anonfun$collect$1$$anonfun$12.apply(RDD.scala:927) at org.apache.spark.SparkContext$$anonfun$runJob$5.apply(SparkContext.scala:1858) at org.apache.spark.SparkContext$$anonfun$runJob$5.apply(SparkContext.scala:1858) at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:66) at org.apache.spark.scheduler.Task.run(Task.scala:89) at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:214) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745) It seems that method MatrixFactorizationModel.recommendProducts is also a transformation.Is there another way to get the recommended movies for userids from a kafka streaming messages? my data is like this: ProducerRecord(topic=test, partition=null, key=null, value={"userid":29694,"movieid":6503,"rating":2.5,"timestamp":1.088441729E9}, timestamp=null) ProducerRecord(topic=test, partition=null, key=null, value={"userid":33063,"movieid":36,"rating":3.0,"timestamp":9.02034829E8}, timestamp=null) ......... -------------------------------- Thanks&Best regards! San.Luo